1. Field of the Invention
The present invention relates to a hydraulic cylinder having eccentric bushings. The hydraulic cylinder has an attachment lug and attachment points for connection with a motor vehicle, for example. The eccentric bushings are disposed in the attachment lug and the attachment points. More particularly, the eccentric bushings can be adjusted to vary the distance between the attachment lug and attachment points for a given position of the piston rod relative to the cylinder, so as to adjust the stroke of the piston rod.
2. Description of the Prior Art
Hydraulic cylinders having adjustable piston rods are known, for example, as disclosed in the German Unexamined Patent Application OS 31 49 628. In practice, however, a problem arises because the distance between the attachment lug and the point of attachment on the cylinder must be precisely maintained, since excessively long or short strokes resulting upon actuation can damage the unit, for instance, a clutch which is actuated by the piston rod. In order to avoid this, the piston rod lug is made adjustable by using a link rod head provided with a thread and fixed in position by a lock nut after adjustment. The adjustment process, however, has to be effected by hand which is cumbersome, time-consuming and expensive.
Another embodiment, in which the attachment lug is arranged directly on the piston rod, has the disadvantage that the distance between the attachment lug and the attachment point includes only very narrow tolerances and once again the adjustment process is very expensive.